I have a 4870x2 in my gaming PC, and it's still the fastest single card money can buy.

A 4870 is a vast, vast improvement in both efficiency, heat dissipation, and performance over a 2600. So, from a quality perspective, I'd say this wins hands down.

The next question I'd ask myself is this: how much is my time worth? Because if you're working hourly doing FCP or other billable projects, you'll sincerely be able to get the done faster with a 4870. The difference in price won't really matter much in the long run ...

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